When I was a kid, I was afraid of ghosts, monsters. I was scared that murderers were right outside my window. Of course we were trained in school to fear the atomic bomb and they tried their damndest to terrify me of hell every week in Sunday school. Yeah, I could go on. I'm guessing that you've got your own list.
Not much about the dark scares me now. I would welcome ghosts. It gets lonely around here.
Thanks to Rob Lorei for the lascivious art.